DESCRIPTION: This proposal is directed towards understanding how the human PAX6 gene and protein are regulated and identifying target genes regulated by PAX6. The aims are 1) to identify the regulatory elements involved in PAX gene transcription; 2) to determine whether PAX6 regulates its own synthesis; 3)to use in vitro mutagenesis for studies of structure and function of the PAX6 protein; 4) to extend analyses of naturally occurring mutations in aniridia patients and examine the consequences of these mutations by constructing PAX6 expression vectors containing these mutations; and 5) to identify the target genes regulated by PAX6.